I think tpmx's point is that the virus would also be less dangerous for them, so getting the vaccine has less chance of having a net benefit for the individual.
Yeah, it was, but I think the argument that the vaccine is a safer option for this crowd is also a pretty persuasive argument.
I'm not exactly in this crowd (I'm 43) but given what I now know about the prevalence of scary long term covid-19 issues ("long haulers") in young people, I would take this vaccine in a heart beat "even" if I were young.